If your horse is suffering from open wounds in its mouth, one of the culprits may be a grass called foxtail. The thistles from foxtail can leave horrible damage throughout your horse’s mouth, causing them discomfort and pain. When one of my horses was dealing with mouth ulcers caused by foxtail, I couldn’t find any information on how to treat it. After asking around, some of my local horse folk gave me a solution that worked great.

So how do you treat a horse suffering from foxtail ulcers in its mouth? The only way to treat mouth ulcers caused by foxtail thistles is to thoroughly remove the thistles from the wounds and apply saline solution as an antiseptic.

Treating foxtail ulcers is no easy task; it’s painful for the horse and you have to maneuver around in their mouth. If you’re ever uncomfortable doing this, the best thing to do is to call the vet. However, if you do decide to treat it yourself, the process is relatively simple and you’ll see results quickly. Keep reading to learn how to recognize that your horse has eaten foxtail, how to properly treat it, and how to keep your horse from ever eating it.

What is Foxtail?

Foxtail is a type of grass that has long stems with seed pods at the tip. If you ever need to identify foxtail, it’s good to know that the seed pods on the end resemble a fox’s tail or a hairy caterpillar.

Foxtail isn’t an uncommon plant, rather it can be seen in the grass in your front yard or in the lovely meadow where you picnic. It may look pretty from afar, but once you’ve seen the damage it can cause to animals, you won’t think twice about having disgust for the grass.

The seedpods in foxtail are surrounded by green and yellow thistles and the seedpods themselves are coated with microscopic barbs. This part of the plant can lodge itself into your horse’s muzzle, gums, and tongue when consumed, causing mouth sores and ulcers.

Horses won’t usually eat foxtail grass outright. They’ll only eat it if the pasture that they’re turned out in lacks the supply of quality grass to graze on, in which case they’ll start eating more plants that they wouldn’t usually eat. Foxtail grass can also be found in lower-quality hay.

Horses are different from other livestock animals in the fact that their digestive systems are much more fragile. There are weeds and types of grasses that cows can eat that horses shouldn’t, foxtail being one of them. Hay suppliers will sometimes cater to both forms of livestock; they’ll have a cleaner field cut for horses while the field with weeds and other grasses will be cut for the cows. However, this isn’t always the case. That’s why it’s important to inspect the quality of hay before you purchase.

How to Tell If Your Horse Has Been Stuck With Foxtail

Since foxtail will mostly affect the inside of the horse’s mouth, it can be easy to miss when your horse has been stuck by the thistles. My POA pony had managed to get himself a one-inch wide foxtail ulcer at the top of his gum above his front teeth. I had to turn up his top lip in order to see it. If it hadn’t been for his profuse drooling, I would have never thought to check his mouth for any problem.

After I realized the extent of the damage that the foxtail had done to his mouth, I have set aside time in my daily routine dedicated to thoroughly checking my horse’s mouth, not necessarily for foxtail, but for anything that may be causing him a problem. If you develop this into your routine, you’ll be able to catch the damage much quicker.

Horses will give subtle cues to explain that there is something wrong with their mouth. Here are some of the things I’ve seen horses do particularly when it comes to dealing with foxtail ulcers in their mouth:

  • The horse will drool profusely.
  • The horse will toss its head 
  • The horse will be uncomfortable with the bit
  • The horse won’t want its muzzle to be touched. 


If you notice these signs in your horse, thoroughly check your horse’s mouth for problems. It’s important to check under the tongue as well as the roof of the mouth. These areas could be affected and no one would ever know. The best way to do this is to grab your horse’s tongue. You may need to get someone to help you, as most horses aren’t fond of this.

If your horse isn’t a fan of you looking in their mouth, you could try twitching their nose. Twitching is when you squeeze the loose part of their top lip in order to give them something else to think about other than you looking in their mouth.

Foxtail wounds will be evident in your horse’s mouth. There will be open wounds with the foxtail thistles sticking out of the area. You will also want to check the horse’s teeth. If you see the thistles and seed pods sticking out from the teeth around the gums, then your horse has clearly been ingesting foxtail.

It’s important to also check the horse’s muzzle for foxtail thistles. It can be hard to tell these thistles apart from the hair. The best way to do this is to look for irritated skin on the muzzle. Chances are if the inside of the horse’s mouth is being affected by the foxtail, the muzzle will be as well.


How to Treat Foxtail Ulcers & Sores In Horses

The most important thing to do once you notice the problem with foxtail is to rid your horse of the option to eat it. This can either mean that you remove them from the field that they were pastured in or you throw out the hay that they have been eating. You can check these sources for traces of foxtail; once again, you can look for the grass that looks like it has the hairy caterpillar at the end of the stalk.

Treating the foxtail ulcers will be no easy or fun task.; you’ll need the right supplies to do it. Here is a list of supplies I use to treat my horse for foxtail ulcers in their mouth:

  • Saline solution 
  • A syringe
  • Tweezers
  • Paper towels 


Have these items ready before you start the process of removing the thistles from the horse’s mouth.


When your horse has foxtail ulcers in its mouth, it will be salivating profusely; this does no good for the ulcer. It keeps the area moist which makes it easier for the foxtail thistles to sink deeper into the skin. I had a veterinarian tell me once that they saw foxtail thistles migrate all the way through the horse’s gums and out through the horse’s mane. This is scary. The thistles will need to be removed to avoid any further damage to your horse.

The first thing you’ll want to do is fill your syringe with the saline solution and squirt it over the affected area. The saline solution works great as an antiseptic, keeping infection out of the wound. The saline will also cause the area to dry out, which in turn will push the thistles pack to the surface. Be careful while doing this, as the saline solution can sting the wound, causing the horse to react.


The next thing you’ll want to do is take the tweezers and pull the thistles from the wound. You’ll be surprised at the number of thistles and seed pods that can pack into the ulcer. In this process, the wound will probably start to bleed so you can use the paper towels or a cloth to wipe the blood away.


The final step is to keep repeating the process until you’ve removed all the foxtail from the wound. If it’s a large enough ulcer, this may take a few days. You’ll notice that one day you’ll remove all the thistles from the wound but more thistles will show up the next day. This happens because the thistles that have lodged into the horse’s body are being drawn to the surface.

Continue to pull the thistles out and apply a saline solution. Keep applying the solution until the wound is completely healed.

If your horse is suffering from sever foxtail ulcers and you’re not having much luck removing the foxtail thistles, then it is time to call the veterinarian. The vet can sedate the horse and remove all the thistles in even the hardest to reach areas.

How to Avoid Foxtail Lesions in Your Horse

How to own a horse on a budget

The best way to avoid foxtail lesions in your horse’s mouth is to first, check their mouth on a daily basis. This will help you catch anything before it becomes too serious. Keep a look out for signs your horse may display to show discomfort in their mouth.

The other way to avoid foxtail is to make sure that your horse has the proper amount of good grass in their field to graze on. When good grass runs out, horses will turn to weeds, bark, and leaves to meet their needed daily intake. Their digestive systems aren’t used to these things, so it may pose even a greater health risk to your horse.

Check hay quality before you buy from a hay supplier. Hay that has foxtail and thorny weeds consistently throughout it will not be good for your horse.


Just like the saline solution I used as an antiseptic for the foxtail ulcers, there are many more natural remedies out there that are very effective at helping your horse. If you’d like to learn more about natural remedies for horses, click here.

Having Trouble With Your Training?

Learn how to gain and maintain your horse’s respect in my latest course!

Carmella Abel, Pro Horse Trainer

Hi! I’m Carmella

My husband and I started Equine Helper to share what we’ve learned about owning and caring for horses. I’ve spent my whole life around horses, and I currently own a POA named Tucker. You can learn more here.

Thank you for reading, and happy trails!

Legal Information

This site is owned and operated by Wild Wire Media LLC.

Equinehelper.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.

This site also participates in other affiliate programs and is compensated for referring traffic and business to these companies.

error: Copying Disabled